kernel.git/tools/perf/util/srcline.h, branch master

perf srcline: Add configuration support for the addr2line style

2026-01-13T19:09:14Z

Allow the addr2line style to be specified on the `perf report` command line or in the .perfconfig file. Committer testing: The methods: # perf probe -x ~/bin/perf -F *__addr2line cmd__addr2line libbfd__addr2line libdw__addr2line llvm__addr2line # So if we configure one of them, say 'addr2line': # perf config addr2line.style=addr2line # perf config addr2line.style addr2line.style=addr2line # And have probes on all of them: # perf probe -x ~/bin/perf *__addr2line Added new events: probe_perf:cmd__addr2line (on *__addr2line in /home/acme/bin/perf) probe_perf:llvm__addr2line (on *__addr2line in /home/acme/bin/perf) probe_perf:libbfd__addr2line (on *__addr2line in /home/acme/bin/perf) probe_perf:libdw__addr2line (on *__addr2line in /home/acme/bin/perf) You can now use it in all perf tools, such as: perf record -e probe_perf:libdw__addr2line -aR sleep 1 # Only the selected method should be used: # perf stat -e probe_perf:*_addr2line perf report -f --dso perf --stdio -s srcfile,srcline # Total Lost Samples: 0 # # Samples: 4K of event 'cpu/cycles/Pu' # Event count (approx.): 5535180842 # # Overhead Source File Source:Line # ........ ............ ............... # 99.04% inlineloop.c inlineloop.c:21 0.46% inlineloop.c inlineloop.c:20 # # (Tip: For hierarchical output, try: perf report --hierarchy) # Performance counter stats for 'perf report -f --dso perf --stdio -s srcfile,srcline': 44 probe_perf:cmd__addr2line 0 probe_perf:llvm__addr2line 0 probe_perf:libbfd__addr2line 0 probe_perf:libdw__addr2line 0.035915611 seconds time elapsed 0.028008000 seconds user 0.009051000 seconds sys # I checked and that is the case for the other methods. Also when using: # perf config addr2line.style=libdw,llvm Performance counter stats for 'perf report -f --dso perf --stdio -s srcfile,srcline': 0 probe_perf:cmd__addr2line 23 probe_perf:llvm__addr2line 0 probe_perf:libbfd__addr2line 44 probe_perf:libdw__addr2line Reviewed-by: James Clark Signed-off-by: Ian Rogers Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Howard Chu Cc: Ingo Molnar Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stephen Brennan Cc: Tony Jones Signed-off-by: Arnaldo Carvalho de Melo

perf addr2line: Add a libdw implementation

2026-01-12T19:23:06Z

Add an implementation of addr2line that uses libdw. Other addr2line implementations are slow, particularly in the case of forking addr2line. Add an implementation that caches the libdw information in the dso and uses it to find the file and line number information. Inline information is supported but because cu_walk_functions_at visits the leaf function last add a inline_list__append_tail to reverse the lists order. Committer testing: # perf probe -x ~/bin/perf libdw__addr2line Added new event: probe_perf:libdw_addr2line (on libdw__addr2line in /home/acme/bin/perf) You can now use it in all perf tools, such as: perf record -e probe_perf:libdw_addr2line -aR sleep 1 # # perf stat -e probe_perf:libdw_addr2line perf report -f --dso perf --stdio -s srcfile,srcline # To display the perf.data header info, please use --header/--header-only options. # # # Total Lost Samples: 0 # # Samples: 4K of event 'cpu/cycles/Pu' # Event count (approx.): 5535180842 # # Overhead Source File Source:Line # ........ ............ ............... # 99.04% inlineloop.c inlineloop.c:21 0.46% inlineloop.c inlineloop.c:20 # # (Tip: For tracepoint events, try: perf report -s trace_fields) # Performance counter stats for 'perf report -f --dso perf --stdio -s srcfile,srcline': 44 probe_perf:libdw_addr2line 0.037260744 seconds time elapsed 0.025299000 seconds user 0.011918000 seconds sys # Adding probes to the other addr2line implementations (llvm__addr2line, libbfd__addr2line and cmd__addr2line) I noticed some fallbacks to the llvm one: Performance counter stats for 'perf report -f --dso perf --stdio -s srcfile,srcline': 44 probe_perf:libdw_addr2line 23 probe_perf:llvm_addr2line 0 probe_perf:libbfd_addr2line 0 probe_perf:cmd_addr2line Something to investigate further, but at least we don't fallback to the cmd based one :-) Reviewed-by: James Clark Signed-off-by: Ian Rogers Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Howard Chu Cc: Ingo Molnar Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stephen Brennan Cc: Tony Jones Signed-off-by: Arnaldo Carvalho de Melo

perf srcline: Fallback between addr2line implementations

2025-10-06T19:47:49Z

Factor the addr2line function implementation into separate source files (addr2line.[ch]) and rename the addr2line function cmd__addr2line. In srcline replace the ifdef-ed addr2line implementations with one that first tries the llvm__addr2line implementation, then the deprecated libbfd__addr2line function and on failure uses cmd__addr2line. If HAVE_LIBLLVM_SUPPORT is enabled the llvm__addr2line will execute against the libLLVM.so it is linked against. If HAVE_LIBLLVM_DYNAMIC is enabled then libperf-llvm.so (that links against libLLVM.so) will be dlopened. If the dlopen succeeds then the behavior should match HAVE_LIBLLVM_SUPPORT. On failure cmd__addr2line is used. The dlopen is only tried once. If HAVE_LIBLLVM_DYNAMIC isn't enabled then llvm__addr2line immediately fails and cmd__addr2line is used. Clean up the dso__free_a2l logic, which is only needed in the non-LLVM version and moved to addr2line.c. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Andi Kleen Cc: Athira Rajeev Cc: Bill Wendling Cc: Charlie Jenkins Cc: Collin Funk Cc: Dmitriy Vyukov Cc: Dr. David Alan Gilbert Cc: Eric Biggers Cc: Haibo Xu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Justin Stitt Cc: Li Huafei Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Peter Zijlstra Cc: Song Liu Cc: Stephen Brennan Signed-off-by: Arnaldo Carvalho de Melo

perf libbfd: Move libbfd functionality to its own file

2025-10-02T18:39:44Z

Move symbolization and srcline libbfd dependencies to a separate libbfd.c. This mirrors moving llvm and capstone code. While this code is deprecated as it is part of BUILD_NONDISTRO license incompatible code, moving the code to its own file minimizes disruption in the main files. disasm_bpf.c is moved to libbfd.c also except for symbol__disassemble_bpf_image which is currently more of a placeholder function rather than something that provides disassembly support. demangle-cxx.cpp code isn't migrated as it is very limited. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Andi Kleen Cc: Athira Rajeev Cc: Bill Wendling Cc: Charlie Jenkins Cc: Collin Funk Cc: Dmitriy Vyukov Cc: Dr. David Alan Gilbert Cc: Eric Biggers Cc: Haibo Xu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Justin Stitt Cc: Li Huafei Cc: Mark Rutland Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Peter Zijlstra Cc: Song Liu Cc: Stephen Brennan Signed-off-by: Arnaldo Carvalho de Melo

perf llvm: Move llvm functionality into its own file

2025-10-02T18:38:23Z

LLVM disassembly support was in disasm.c and addr2line support in srcline.c. Move support out of these files into llvm.[ch] and remove LLVM includes from those files. As disassembly routines can fail, make failure the only option without HAVE_LIBLLVM_SUPPORT. For simplicity's sake, duplicate the read_symbol utility function. The intent with moving LLVM support into a single file is that dynamic support, using dlopen for libllvm, can be added in later patches. This can potentially always succeed or fail, so relying on ifdefs isn't sufficient. Using dlopen is a useful option to minimize the perf tools dependencies and potentially size. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Andi Kleen Cc: Athira Rajeev Cc: Bill Wendling Cc: Charlie Jenkins Cc: Collin Funk Cc: Dmitriy Vyukov Cc: Dr. David Alan Gilbert Cc: Eric Biggers Cc: Haibo Xu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Justin Stitt Cc: Li Huafei Cc: Mark Rutland Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Peter Zijlstra Cc: Song Liu Cc: Stephen Brennan Signed-off-by: Arnaldo Carvalho de Melo

perf srcline: Add a timeout to reading from addr2line

2023-06-14T21:19:06Z

addr2line may fail to send expected values causing perf to wait indefinitely. Add a 1 second timeout (twice the timeout for reading from /proc/pid/maps) so that such reads don't cause perf to appear to lock up. There are already checks that the file for addr2line contains a debug section but this isn't always sufficient. The problem was observed when a valid elf file would set the configuration for binutils addr2line, then a later read of vmlinux with ELF debug sections would cause a failing write/read which would block indefinitely. As a service to future readers, if the io hits eof or an error, cleanup the addr2line process. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ingo Molnar Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Yang Jihong Link: https://lore.kernel.org/r/20230608061812.3715566-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf srcline: Optimize comparision against SRCLINE_UNKNOWN

2023-06-12T21:17:00Z

This is a string constant that gets returned and then strcmp() around, we can instead just do a pointer comparision. That requires a new global variable to comply with these warnings from some versions of clang and gcc: 41 68.95 fedora:rawhide : FAIL clang version 16.0.4 (Fedora 16.0.4-1.fc39) result of comparison against a string literal is unspecified (use an explicit string comparison function instead) [-Werror,-Wstring-compare] if (start_line != SRCLINE_UNKNOWN && ^ ~~~~~~~~~~~~~~~ 41 Ack comments: Agreed, the strcmps make me nervous as they won't distinguish heap from a global meaning we could end up with things like pointers to freed memory. The comparison with the global is always going to be same imo. Acked-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ali Saidi Cc: Andi Kleen Cc: Athira Rajeev Cc: Brian Robbins Cc: Changbin Du Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: Fangrui Song Cc: German Gomez Cc: Ingo Molnar Cc: Ivan Babrou Cc: James Clark Cc: Jing Zhang Cc: Jiri Olsa Cc: John Garry Cc: K Prateek Nayak Cc: Kan Liang Cc: Leo Yan Cc: Liam Howlett Cc: Mark Rutland Cc: Miguel Ojeda Cc: Mike Leach Cc: Namhyung Kim Cc: Naveen N. Rao Cc: Peter Zijlstra Cc: Ravi Bangoria Cc: Sean Christopherson Cc: Steinar H. Gunderson Cc: Suzuki Poulouse Cc: Wenyu Liu Cc: Will Deacon Cc: Yang Jihong Cc: Ye Xingchen Cc: Yuan Can Link: https://lore.kernel.org/lkml/ZIcoJytUEz4UgQYR@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf srcline: Change free_srcline to zfree_srcline

2023-06-12T18:57:54Z

Make use after free more unlikely. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ali Saidi Cc: Andi Kleen Cc: Athira Rajeev Cc: Brian Robbins Cc: Changbin Du Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: Fangrui Song Cc: German Gomez Cc: Ingo Molnar Cc: Ivan Babrou Cc: James Clark Cc: Jing Zhang Cc: Jiri Olsa Cc: John Garry Cc: K Prateek Nayak Cc: Kan Liang Cc: Leo Yan Cc: Liam Howlett Cc: Mark Rutland Cc: Miguel Ojeda Cc: Mike Leach Cc: Namhyung Kim Cc: Naveen N. Rao Cc: Peter Zijlstra Cc: Ravi Bangoria Cc: Sean Christopherson Cc: Steinar H. Gunderson Cc: Suzuki Poulouse Cc: Wenyu Liu Cc: Will Deacon Cc: Yang Jihong Cc: Ye Xingchen Cc: Yuan Can Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20230608232823.4027869-26-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf callchain: Use cached rbtrees

2019-01-25T14:12:09Z

At the cost of an extra pointer, we can avoid the O(logN) cost of finding the first element in the tree (smallest node), which is something required for nearly every in/srcline callchain node deletion (in/srcline__tree_delete()). Signed-off-by: Davidlohr Bueso Tested-by: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lkml.kernel.org/r/20181206191819.30182-4-dave@stgolabs.net Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Support 'srccode' output

2018-12-17T17:57:07Z

When looking at PT or brstackinsn traces with 'perf script' it can be very useful to see the source code. This adds a simple facility to print them with 'perf script', if the information is available through dwarf % perf record ... % perf script -F insn,ip,sym,srccode ... 4004c6 main 5 for (i = 0; i < 10000000; i++) 4004cd main 5 for (i = 0; i < 10000000; i++) 4004c6 main 5 for (i = 0; i < 10000000; i++) 4004cd main 5 for (i = 0; i < 10000000; i++) 4004cd main 5 for (i = 0; i < 10000000; i++) 4004cd main 5 for (i = 0; i < 10000000; i++) 4004cd main 5 for (i = 0; i < 10000000; i++) 4004cd main 5 for (i = 0; i < 10000000; i++) 4004b3 main 6 v++; % perf record -b ... % perf script -F insn,ip,sym,srccode,brstackinsn ... main+22: 0000000000400543 insn: e8 ca ff ff ff # PRED |18 f1(); f1: 0000000000400512 insn: 55 |10 { 0000000000400513 insn: 48 89 e5 0000000000400516 insn: b8 00 00 00 00 |11 f2(); 000000000040051b insn: e8 d6 ff ff ff # PRED f2: 00000000004004f6 insn: 55 |5 { 00000000004004f7 insn: 48 89 e5 00000000004004fa insn: 8b 05 2c 0b 20 00 |6 c = a / b; 0000000000400500 insn: 8b 0d 2a 0b 20 00 0000000000400506 insn: 99 0000000000400507 insn: f7 f9 0000000000400509 insn: 89 05 29 0b 20 00 000000000040050f insn: 90 |7 } 0000000000400510 insn: 5d 0000000000400511 insn: c3 # PRED f1+14: 0000000000400520 insn: b8 00 00 00 00 |12 f2(); 0000000000400525 insn: e8 cc ff ff ff # PRED f2: 00000000004004f6 insn: 55 |5 { 00000000004004f7 insn: 48 89 e5 00000000004004fa insn: 8b 05 2c 0b 20 00 |6 c = a / b; Not supported for callchains currently, would need some layout changes there. Committer notes: Fixed the build on Alpine Linux (3.4 .. 3.8) by addressing this warning: In file included from util/srccode.c:19:0: /usr/include/sys/fcntl.h:1:2: error: #warning redirecting incorrect #include to [-Werror=cpp] #warning redirecting incorrect #include to ^~~~~~~ cc1: all warnings being treated as errors Signed-off-by: Andi Kleen Tested-by: Jiri Olsa Link: http://lkml.kernel.org/r/20181204001848.24769-1-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo